Kidney cancer develops when abnormal cells grow uncontrollably in the kidneys, the organs responsible for filtering waste and excess fluids from the blood. The most common type is renal cell carcinoma (RCC). In its early stages, kidney cancer may not cause symptoms. As it progresses, symptoms may include blood in the urine, persistent pain in the side or back, a lump in the abdomen, unexplained weight loss, fatigue, or loss of appetite. Early diagnosis is important for successful treatment. Depending on the stage of the disease, treatment may include minimally invasive or robotic kidney surgery, partial or radical nephrectomy, targeted therapy, immunotherapy, or, in selected cases, radiation therapy.